[Archrms]

I think I found the culprit. I pulled the reverser off the back of the speedo. The reverser has a plastic insert that transmits the rotation from the reverser to the speedo - and it appears to have twisted and snapped off, with part of it still in the speedo. I need to find something small enough to fit into the rear of the speedo and try to extract the plastic insert that broke off. Then I can determine if the speedo rotates or is locked up (which would explain why the plastic insert twisted and broke).